In a next-generation portable terminal system referred to as LTE, orthogonal frequency division multiple access (OFDMA) is used in downlink, and single carrier frequency division multiple access (SC-FDMA) is used in uplink. In LTE, voice communication is supported by means of voice over Internet protocol (VoIP), and a bandwidth of the signal is variable among 1.4 MHz, 3 MHz, 5 MHz, 10 MHz, 15 MHz, and 20 MHz.
When a transmission signal bandwidth is widened in SC-FDMA used in LTE, a frequency diversity effect of averaging variation of a propagation path in a frequency domain is enhanced. However, when the bandwidth is extended more than necessary, accuracy in estimation of a propagation path is degraded, and for this reason, a reception characteristic deteriorates. Thus, as shown in FIG. 23, resource blocks (RBs) in a frequency axis direction and subframes in a time axis direction are appropriately allocated to respective users according to an information rate of transmission traffic.
FIG. 24 is an explanatory diagram obtained by simplifying content specified in TABLE. 5.6-1 of Section 5.6 in 3GPP TS36.101. In FIG. 24, a plurality of RBs are arranged in a range of a communication path bandwidths (channel bandwidth). Also, a data transmission bandwidth, that is, a bandwidth of a signal actually used in transmission, is shown by actually used RBs (active resource blocks). As a relationship between the bandwidth of the used signal and RBs of an entire communication path bandwidth, an arrangement of a data transmission bandwidth (transmission bandwidth configuration) is shown. The number of all RBs capable of transmission, that is, the number of all RBs included in a communication path bandwidth will be referred to as a “transmission bandwidth configuration” below, like the “arrangement of a data transmission bandwidth.”
FIG. 24 shows that a transmission bandwidth configuration is 25 in a band of 5 MHz. In other words, the maximum number of RBs capable of transmission in a band of 5 MHz is 25. Among these maximum 25 RBs, actually used RBs are eight of block numbers RB#8 to #15.
A method of determining a reference band and adjusting transmission power such that transmission power for a time of the maximum number of RBs becomes an arbitrary power, such as a transmission power adjustment method that is generally employed in a transmission device used in such LTE, and the like, is known (for example, Patent Literature 1). For example, assuming that a reference band is 5 MHz, and used RBs are a maximum of 25 RBs, transmission power is adjusted to be, for example, +23 decibel milliwatts [dBm] (the maximum transmission power specified in TABLE 6.6.2-1 of Section 6.2 in 3GPP TS36.101). In addition, when a bandwidth becomes 1.4 MHz, 3 Hz, 10 MHz, 15 MHz, and 20 MHz, transmission power of a case in which a bandwidth varies is finely adjusted by multiplying by a certain coefficient.